1. Field of the Invention
One embodiment of the present invention relates to an electronic device. In particular, one embodiment of the present invention relates to a wearable electronic device, for example, an arm-worn electronic device.
Note that one embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, an input device (e.g., a touch sensor), an input/output device (e.g., a touch panel), a driving method thereof, and a manufacturing method thereof.
In this specification and the like, electronic devices mean all devices which operate by being supplied with electric power, and electro-optical devices, information terminal devices, and the like including power sources (e.g., power storage devices) are all electronic devices.
In this specification and the like, power storage devices mean all elements and devices that have a function of storing electric power, and a storage battery (also referred to as a secondary battery) such as a lithium-ion secondary battery, a lithium-ion capacitor, an electric double layer capacitor, and the like are all power storage devices.
2. Description of the Related Art
Display devices and electronic devices used while being worn on human bodies have recently been developed and are referred to as wearable displays, wearable devices, and the like. For example, head-mounted displays which are mounted on heads and smart watches which are worn on arms have been developed.
Patent Document 1 discloses a ring-shaped display device that can be used while being worn on a human body.
Since the wearable devices are used while being worn on human bodies, a reduction in weight of the entire device including a display panel, a driver circuit, and a power source is required to achieve high portability and comfort of wearing the wearable devices.
Wearable devices are generally equipped with power storage devices. For example, lithium-ion secondary batteries have been actively developed because the capacity thereof can be increased and the size thereof can be reduced.
Light-emitting elements utilizing electroluminescence (also referred to as EL elements) have features of the ease of being thin, lightweight, and flexible, high-speed response to input signals, capability of DC low voltage driving, and the like, and thus are display elements which are preferably used in wearable displays.